1. Field of the Invention
The invention relates to a solder joint material and a method of manufacturing the solder joint material.
2. Description of the Related Art
Lead is conventionally contained in solder which is a joint material used for electrically joining components of electric/electronic equipments. According to an increase in environmental awareness, however, a move to restrict the use of lead, of which toxicity to human body has been identified, has spread especially in Europe since around 2003, and Pb-free alternative materials not containing lead have been developed.
The solder is classified into three types, high-, mid- and low-temperature solders, according to the melting temperature. Of those, mid- and low-temperature Pb-free solders have been already put to practical use but there is no high-temperature Pb-free solder which satisfies all market demands (heat resistance at 260° C., high thermal conduction, joint reliability and low cost).
In response to the demand for development of high-temperature Pb-free solders which satisfy all market demands, a Pb-free joint material disclosed in JP-A-2012-71347 was developed.